Method of curing or vulcanizing the outer shoes or casings of pneumatic tires.



E. HOPKINSON a; T. MIDGLEY.

' 'MTID 0F OURING 0R VULOANIZING THE OUTER SHOES 0R GASINGS 0F PNEUMATIG TIRES..

APPLICATION FILED-DEU. 19, 1905.

901,007. l Patented oct. 13,1908.

L/iwww ERNEST noriirNsoN, -eirfEAsT ORANGE,

UNITEnjsTA'rEswiTENr OFFICE.

FORD, CON NEcTlCUTgsAiD norKrNsoN AssreNoE To THE HAETEORDEUBEER wenns COMPANY, oE-HARTFORD, CONNECTICUT,

A CORPORATION OF CONNECTICUT.

METHOD oF Cimino 'on' vUncANIzING THE OUTER SHOES' on eAsrNes or Primm/mafie TIRES,

To all whom 'it may concern:

Be it'known that we, ERNEST HorErNsON and THOMAS MIDGLEY, citizens' of the United States, residing in East Orange, in the county of Essex and State Of New Jersey, and in Hartford, in' the county of Hartford and State of Connecticut, respectively, have invented a new and useful Improvement in Methods of Curing or Vulcanizing the Outer Shoes or Casings of Pneumatic Tires, of which the following is a specification.

This invention relates to a method of euring or vulcanizing .the outer shoes or casings of pneumatic tires for vehicles, and it has for its Object the improvement in the method of vulcanizing or curing such Outer sheaths or casings by means of what is known as an open heat, whereby the curing or vulcaniz ing may be effected in a4 single exposure to live steam.

The method forming the present invention will be hereinafter described in detail in connection with the accompanying drawings in which we have illustrated apparatus adapted for use in.practicing the process.

In the drawings: Figure 1 is a View in transverse section through the entire apparatus in operative relation to a tire shoe or casing. Fig. 2 is a view in side elevation of one form of collapsible core. viewl in side elevation (with part broken away) of another form of core. Fig. 4 is a detail view in cross-section through a strip of spring metal adapted for use in making a core of the character illustrated in Fig. 3.

The curing Or. vulcanizing of outer shoes or casings of pneumatic tires for vehicles has hitherto been accomplished either'- by a single exposure to heat in a metallic mold completely covering the entire shoe or casing, or by curing or vulcanizing in a mold a skeleton or carcass of the outer shoe or casing, then artially curing a separate tread strip, and inally applying the partially cured tread strip to the skeleton or carcass by means of vulcanizable cement and exposing the entire outer shoe or casing thus made, up, to the action of live steamin a suitable chamber. In this latter method of curing, the tre-ad strip receives its iinal curing treatment withk live steam, and ihe vulcanizing of the cement by which the tread strip is secured is Specification of Letters Patent. Application led December 19, 1905'.4 Serial No. 292,444.

effected by means necessary to hold the shoe or casing in proper Vshape during the action of the steam ani. to

.margins thereof. member 2, and the clamping members 3 con- Fig. 3 1s alsuitable manner,

" Patented Oct. 1s,- 1908.

of the live steam, but the curing of the other portions of the tire is effected in the mold, and the' furtherl action, if any, of the live steam thereon is apt to be detrimental. `In anyevent, three successive operations are re uired to eHect -the complete curing or'vu casing.

In order to effect they curing or vulcanization of the tire shoe or casing by means of live steam in the openheatl process, it is provide means-for giving form to the margins of the shoe or casing during the curing or vulcanizingoperation, butto leave the tread portion of the shoe or casingeX osed to the direct action' of the steam. o meet all these conditions, ,we preferably introduce within the uncured shoe or casing S a core 1 of suitable construction and proper cross section, and place between the margins of the sheath or -casin an abut-ment member 2 against which t e margl-)in's are forced by.

means of clam ing mem ers 3arranged external to the s oe or caslng ad acent to the The core 1, t ie abutment stitute a Vmold for the margins of the sheath or casing and the portions adjacent thereto. The clamping'members 3 are secured in any as by screws 4 extending through li 's or webs 5 extending inwardly from the' c aniping members, and/'rings 6 havingdeep channels 7 formed in their exposed side surfaces are fitted against the clamping members 3, or formed integral therewith, if preferred. The exposed lateral faces-of the clamping members are tangential at their outer margins to the surface of the tire shoe canization of the shoe or N Ew JERSEY, AND THOMAS MrnGLEY, or HART-V or casing, so that a cover 8 of orous material, such as duck or other textile fabric, extending over the tire shoe or casing clamping members, willlie in close contact, with all the 4exposed portions o f the shoe or casing. To place the cover 8 under the tension required to produce upon the shoe or casing the desired pressure, two anuuli Q are em 'loyed to force the cover into the channel 7, and a suitable number of clamps or equivalent devices are used .to press the annuli E) into the position shown in Figx 1. '.lhe

and the not covered by clam 10 illustrated in the drawings is one of a We l-known type which may be employed for this .pur ose, but others'may be substituted instea( if desired. f

VVhen the shoe or casing has been mounted u j on the core 1, clamped in position b means ci) the abutment member 2 and the c amping members 3, covered with the covering 8, and subjected to pressure by lacing the cover under tension, as shown, t e shoe or casing with the securing devices or cover is introduced into the drum or chamber for vulcanizing and is there subjected to the action of live steam, which penetrates the porous materialof the cover 8 and acts directly upon the portions of the shoe or casing which are the clamping members 3. The ortions of the shoe or casing covered by the c amping members 3 receive enough heat through these clampingfmembers, which being made of metal are good conductors, and in this Way the curing of the entire shoe or casing is effected at a single operation by which the tread, upon which the most severe Wear is received, is cured by the direct action 'of live steam, while the'other portions of the tire are cured by ing members.

By. means of the improved process, the number ofeoperations necessaryto elect the curing or vulcanization of the tire shoe or casing is reduced to one, and the danger of overcuring portions of the shoe or casing is entirely eliminated.

The apparatus em loyed in carrying out the process or metho above outlined may be varied considerably, and I have illustrated only ty )ical apparatus for the purpose. The core 1 illustrated in Fig. 1 is preferably made in three sections connected together by means of hinges 10 as shown in Fig. 2 and provided with a latch 11 to secure the sections in proper relation when the core is in position within the tire shoe or easing. Instead of this form of core, one made ofa strip 12 of spring metal, having the edges beveled as at. 13 in Fig. 4, may be employed. The strip 13 is formed into a spiral of uniform diameter throughout with 'Whirls overlapped as indicated, and the ends of the strips of metal are then secured to ether so as to form an endless structure, which has suflicient compressidry heat through the clampbility and expansibility to be easily introduced within a tire shoe or casing and removed therefrom.

The cover 8, which is employed to hold the tread portion of the shoe or casing in proper shape and prevent the rubber from running, is preferably formed ol' a long and com )aratively narrow strip of fabric bound spnally around the shoe or casing and the supporting and securing devices, butthis form of cover may be dis )ensed with and others employed, if referredi.

laving thus described our invention, what We claim is 1. The method of vulcanizing or curing outer shoes or casings for pneumatic tires i or vehicles which consists in supporting the shoe or casing upon a core, placing an abutment member between the margins ol" the shoe or casing, clamping the shoe or easing firmly upon the core and against the abutment member, but leaving the tread portion of the shoe or casing exposed, placing a coveri of textile fabric over the cx iosed tread portion ofthe shoe or casing an in contact therewith, and in subjecting the shoe or Ycasing so supported and covered to the action of vulcanizing heat.

2. The method of curing or vulcanizing outer shoes or casings for pneumatic tires, which consists in supporting and clamping the shoe or lcasing so as to hold it in the form which it is intended to retain when vulcanized and leaving the tread portion of the easing above the clam ing means exposed, placing a covering oZ porous materialover such exposed portion of the casing and in contact therewith and also over the outer portions at least of the outer sides of the clamping means, subjectiniT such covering to lateral tension applied at tlie sides below the periphen'es of the clamping means to create a pressure on the shoe oneasing, and exposing the shoe or casing so covered to the action of live steam. y

In testimony whereof, we have signed our names in the presence of two witnesses.

ERNEST HOPKINSUN; THOMAS MIDGLEY.'

and supported Witnesses:

BAXTER MoR'roN, H. RICHARD. Wonen. 

